The invention concerns an internal combustion engine with a motor block and a longitudinally extended anti-rotation guide, which includes openings arranged sequentially at apportioned distances from one another, to receive valve lifters, and the anti-rotation guide is affixed in a receiving groove of the motor block.
Anti-rotation guides have been already installed in internal combustion engine for the orientation and the prevention of the turning of roller tappets. In such installations, the guide is fastened on the motor block with screws, as is disclosed by U.S. Pat. No. 5,088,455 wherein a known anti-rotation guide is described.
In DE 197 12 610 A1, wherein an anti-rotation guide of an internal combustion engine is presented, the explanation discloses that internal combustion engines normally possess roller tappets, which engage cam lobes of a cam shaft. The tappets are not to rotate about each of their respective axes, because the rollers on the tappets must remain in the same plane with the cam lobes. For this reason, the tappets in the cylinder block of the internal combustion engine are equipped with special holding devices in an appropriate manner and their rotation is prevented. In the case of the fastening of such a holding device with screws on the motor block, for the securement of the tappet against turning, the disadvantage can be mentioned, that for this installation, an additional assembly time is necessary. Besides that, additional costs arise because of the necessity of boring holes for the screws and to internally cut the required female threads.
In the publication DE 197 12 610, and on the given grounds, the proposal was made to attach an elastic prestressed element to the longitudinally extended body of the holding apparatus, in order to affix the apparatus between the cylinder block and the cylinder head. That disclosure provides is a leaf spring, serving as an elastic, pre-stressed element, which is accepted in a groove provided therefor in the anti-rotation guide.
The invention has the purpose of reducing the number of construction components in an anti-rotation guide, where an internal combustion engine is concerned, and to simplify the assembly of the same.
This purpose will be achieved, in accordance with the invention, in that the guide is to be manufactured as an injection molded component. This component is to be molded as one piece, with an elastic, deflectable or deformable clip, which engages a complementary shape on a motor block. In this way, there is made available an alternative to the screwed fastenings customarily found on the anti-rotation guide. The use of a molded clip can be advantageous, if no space is available for a screw fastening. By means of a clipping connection of the anti-rotation guide in a complementary receiving means on the motor block, and the associated elimination of screw fastenings, there is brought about a less complicated assembly and inventory control of parts. Also, the addition to the motor block and the mounting of the guide thereon is simpler, so that the costs of these operations are reduced. Complementary contours can be designed into the anti-rotation guide, in such a way, that upon the mounting of the cylinder heads, the guide can be brought into its correct position and retained there. For compensation of tolerances, these complementary contours can be executed by at least one, reversely bent, spring yoke.